Agreed. Parts* & Service are two giant profit centers that take a big hit with EVs, which is one of the reasons dealers have been so resistant to selling them for years now. The actual manufacturing doesn't get a whole lot easier, though, which is one of the reasons there have been so many EV startup failures.

*Note: Parts here means only powertrain parts. Tesla, for example, is notorious for having massive delays in repair parts availability for things like doors, trim, and windows.

Companies like Toyota and VW roll out a new chassis once or twice a decade and you see some amount of shared powertrain parts everywhere from economy level to high-end performance and luxury models. They're really good at building common skeletons where every part of a car is pieced together like interchangeable legos. The research cost is high but the investment is inevitably returned with the scale and time available to these entities.